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2008 hummer h3 3.7 swap engine to 5.7

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Old 02-24-2020, 11:40 AM
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Default 2008 hummer h3 3.7 swap engine to 5.7

Hello guys am new here plz i need some help i have 5.7 suburban with transmission and all the wiring i just want to know is it hard to swap the engine harness and trans cos the meqanique said u need the alpha engine harness i couldnt understand why if i have the 5.7 all harness and computer engine why i need to get the alpha h3 harness if u plz can help me thx
 
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Old 02-24-2020, 11:50 AM
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[QUOTE=Franky;370913]Hello guys am new here plz i need some help i have 5.7 suburban with transmission and all the wiring i just want to know is it hard to swap the engine harness and trans cos the meqanique said u need the alpha engine harness i couldnt understand why if i have the 5.7 all harness and computer engine why i need to get the alpha h3 harness if u plz can help me thx i know this post was posted but last one i saw 2007 so maybe any new and easy ideas thx
 
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Old 02-24-2020, 12:13 PM
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You cannot simply take whatever GM V8 you have and plug it into an H3. It has to bolt to the transmission, motor mounts and clear the front suspension.... the easy part. Then it has to be programmed to the vehicle and be attached to the electrical harnesses.
 
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Old 02-25-2020, 06:42 AM
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Thx Doc olds for replying i really like my hummer h3 2008 and really need to swap for bigger engine and trans any easy swap for my h3 engine and transmission thx
 
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Old 02-25-2020, 06:49 AM
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I totally understand how you feel Franky, maybe get a H3 Alpha engine and trans with harness? Or mod your current engine I5, Air Doc's intake, PCM Tune, Ported Throttle Body, Iridium Spark plugs, Performance Airfilter, Catback exhaust, E-Fan.....anything I'm missing here guys? With those mods you'd probably save money and you I5 maybe beat out that V8 hehe
 
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Old 02-25-2020, 12:58 PM
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if you need to purchase an alpha drive train to swap in. common sense should tell you that you just replace the entire vehicle with an alpha.
 
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Old 02-25-2020, 01:30 PM
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Unless you have a mechanic that can do it for cheap
 
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Old 02-25-2020, 03:34 PM
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the problem with conversions is only one person knows how to troubleshoot it.... and if it is not you then your stuck.
 
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Old 02-26-2020, 05:19 AM
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Here no need for this all explanation thell mount ur engine and trans then theyll hook the harness and leave the original one also will hook it for all electic stuff and it works plus the 5.7 vortec with all the wire and mounting for 400$ kinda cheap plus the meqanique will take 300$ just for swapping not electeicity he will give u the H3 woeks without electeicity cheap ahhh
 
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Old 02-26-2020, 08:12 AM
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Originally Posted by Franky
Here no need for this all explanation thell mount ur engine and trans then theyll hook the harness and leave the original one also will hook it for all electic stuff and it works plus the 5.7 vortec with all the wire and mounting for 400$ kinda cheap plus the meqanique will take 300$ just for swapping not electeicity he will give u the H3 woeks without electeicity cheap ahhh
An 80s or 90s 5.7L Vortec! That won't work without a LOT OF WORK! An 80s or 90s 5.7L Vortec!
Best of luck...
Just for your information, H3/H3T Alpha is a 5.3L all aluminum LS.
 


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